I receive a fair share of emails from people with Model I Power Supply issues. While common wisdom is to cut open those supplies and replace the fuse, sometimes that is not possible, that is not the problem, or the individual is missing a supply altogether. I had asked Ian Mavric to look into the matter and Ian has now advised that Dean Bear has designed a replacement power supply for the Model I. It has enough power to drive both the Model I and the Expansion Interface, so two will not be needed. The graphic to the left are designs for a 120V and a 240V, depending on your need. Of course, I have not tested these, and have no idea if they work (Dean has been running his for over a year and Ian and Dean will be testing these schematics shortly), so build/use at your own risk.

“Metatronics (a subsidiary of Meta Technologies Corp., as of September 1, 1981) introduces a unique device allowing the connection of as many as 8 disk drives to a TRS-80 Model I computer. Its integrated design is compatible with application software running under VTOS, LDOS, NEWDOS/80, NEWDOS+ and TRSDOS 2.3. Features include a U.L.-approved power supply, power-monitor LED, operating environment protection circuitry, high-impact metal case and gold-plated contacts. Complete with instructions and patch program diskette for configuring your favorite operating system.”

Glenn Emelko advised …

I designed this product for MTC, and did all of the OS patches for TRSDOS, LDOS, and Newdos/80 personally. The device decoded the four drive address lines so that codes 1, 2, 4, and 8 (0001, 0010, 0100, and 1000) addressed the first four drives 0-3 directly. Other combinations of the drive select lines then selected subsequent drives allowing addressing of drives 4 to 7 (iirc it was 0011, 0101, 0110, and 0111 respectively), and we internally experimented with a 15 drive system using 8,9,A..E for the next drive numbers but never released it that way. One code 0000 was reserved for no drives selected. The operating system patches were tricky but once complete it worked great.

Arnold Gross has let me know that he and Rik Pierce hold the copyright to NAME THAT SONG (a musical quiz game) and that they are permitting it to be available for posting for everyone to enjoy.

Since TRS-80 disks are very unlikely to hold data for the (approximately) 110 years of copyright; if anyone else is holding a copyright in TRS-80 software that they are willing to allow people to download, please contact me.

Kurt Baumgardner wrote a short BASIC program to allow those with Model I’s to dump their ROM’s to cassette if that is their only option. Kurt advises that it needs 16K of RAM and takes a little less than 3 and a half minutes to run. He did not test it on a Model III but assumes, at the very least, that the ROM line would need to be changed from ROM=12 to ROM=14

In hopes of answering all of the questions which have arisen from the realization that there are 4 versions of the Model I ROM and we (at the time) had only 1 of them, Matthew Reed, author of the amazing TRS32 emulator, has posted a brief explanation of the ROM versions.

Important Note:

Is there an eBay store for TRS-80's?

Yes - Three

Dale Frantz has had his "TRS80sAndMore" store on eBay for 18 years, with 100% positive feeback and 100% money back guarantee. Check out the store HERE!.
Trash Talk Podcaster Ian Mavric has also been on eBay for more than 18 years also with 100% feedback and a long history with TRS-80s going back to the 1980s. Timely, reliable shipping from Australia. Check out the store HERE!.
Bra McCartney also has a Store.

Do you have TRS-80 Disks or Tapes?

If you have Model I, III or 4 TRS-80 disks lying around, you may want to think about sending them in. If the data is intact, I can read them into “virtual disk files” (DMK files) which will serve not only to archive the disk forever, but would also allow you to use those virtual disks in an emulator on your current computer, and to extract the data to your current computer if you wanted to.

The media on these disks and tapes were not intended to hold data for 35+ years and the data will not last forever. If you do have disks lying around, I would encourage you to contact me.